Fig. 1

Growth characteristics of P32 and P605 cell suspension cultures. a and e Images of 1-month-old type II friable embryogenic calli-derived inflorescences of P32 (a) and P605 (e). b, f Flasks containing 7-day-old P32 and P605 cell suspension cultured in MSO medium, respectively. c–h Laser scanning confocal micrographs of viable single and clustered cells stained with FDA in green. c, g Bright-field micrographs of P32 and P605 cells, respectively. d, h FDA staining micrographs of P32 and P605 cells, respectively. i, j Cell density and viability as evaluated with fresh weight (FW) and FDA staining, respectively. Gray circle graph represents P32 cell density. Black circles graph represents P605 cell density. Gray columns represent the percentage of viable P32 cells. Black columns represent the percentage of viable P605 cells. Experiments were done in triplicate. Error bars represent the mean ± standard error (SE). Different letters denote a statistically significant difference among means at a p value < 0.05 according to one-way ANOVA (Tukey’s test). White arrowhead indicated dividing cells. Bars = 0.5 cm in a, e; 50 µm in c–h